Drafting apparatus



Oct. 8, 1940. R. H. GARNER DRAFTING APPARATUS Filed March 17, 1959 2sheets-sheet 1 EWIIIIWIIWIWNUINWHD,

INVENTOR. Russe H. Garner.

ATTORNE Oct. s, 1940.

Rl H. GARNER DRAFTING APPARATUS Filed March 17, 1939 2 Sheets-Sheet 2FTE. E n

1N VENTOR. Russe H. Garner'.

ATTORN Y.

Patented ci. 8, i940 Unire stares ein-re 'r f Application March 17,

, 6 Claims.

This invention relates to drafting instruments.

The general object of the invention is to provide an improved universaldrafting machine.

Another object of the invention is to provide an improved draftingmachine wherein parallel movements of the parts are provided b-y a novelpulleyvarm construction and wherein the parts may be made of metalstampings.

A further object of the invention is to provide a-universal draftingmachine including a novel protractor head assembly.

An additional object of the invention is to provide novel means fortightening the flexible coupling member used in a drafting machine.

Other objects and the advantages of this invention will be apparent fromthe following description taken in connection with the accompanyingdrawings, wherein:

Fig. l is a top plan view of my improved universal drafting machine;

Fig. 2 is a side view of the drafting machine;

Fig. 3 is 'an enlarged section taken on line 3-3 of Fig. l

Fig. 4 is a section taken on line 6 6 ci Fig. 3;

Fig. 4A is a` section taken on line 13A-4A of Fig. 4;

Fig. 5 is an enlarged side elevation partly in section of the mastportion of the drafting machine;

Fig. 6 is an enlarged section taken on line --S of Fig. 1;

Fig. 7 is an enlarged section taken on line 'l-- of Fig. 1, but with thearms vertically aligned;

Fig. 8 is an enlarged section taken on line 8 8 of Fig. 1;

Fig. 9 is a top pla-n View of the protractor member with the supportingarm removed;

Fig. l is an enlarged fragmentary section taken on line Ill-Il) of Fig.9;

Fig. 11 is an enlarged fragment-ary section taken on line I I--II ofFig. 9;

Fig. l2 is an enlarged fragmentary section taken on line I2-i2 of Fig.8;

Fig. 13 is a section taken on line i3-I3 of Fig. 7;

Fig. 14 is a fragmentary section taken on line Ill-Iiof Fig. 8; and

Fig. l is an enlarged fragmentary longitudinal sectional View of theupper section of the elbow portion showing a modified form of brakeconstruction.

Referring to the drawings by reference characters I have indicated myimproved drafting machine generally at i6. As shown the machine Iincludes a mast portion indicated generally at I2,

1939, Serial N0. 262,392 (Cl. 33-79) an elbow portion indicatedgenerally at I3 and a head portion indicated .generally at Iii.

The mast portion I2 is shown in detail in Figs. 5 and 6 and includes asubstantially triangularly shaped base member l5 which is provided with5 a pair of clamps I6 secured to the base by screws I l. The clamps I6include threaded members I8 having heads I9 thereon to engage a drawingtable or other support to hold the drafting machine in an operativeposition.

On the base member i5 I provide a secondary base member 2li. The basemember I5 includes a plurality of upwardly directed protuberancesv 2!and the secondary base includes a plurality of downwardly directedprotuberances 22 which engage the protuberances 2l. The protuberances 2|each has a suitable threaded aperture therein and the protuberances 22each has a suitable aperture therein to receive a screw 23 to secure thesecondary base 2U to the base I5.

i An adjusting screw 24 is provided so that when the screws 23 areloosened the screw 24 may be moved to shift the secondary base i5 to-anadjusted position after. which the screws 23 are tightened to firmlyclamp the secondary base 2B to the base I5. The secondary base I5 isapertured as at 425 to receive a vertical post member 25 which issecuredto the base I5 bya threaded washer '2.1 and a nut 28 engaging a threadedportion at the lower end of the post. v

Themast portion I2 further includes an arm supporting bracket member 30which comprises an upper member 3l and a lower member 32. The uppermember' 3l comprises a body portion 33 which includes a top wall 34having depending side flanges 35 which atone end merge into a.semi-cylindrical portion 36. Depending from the top wall 34 I provide aninverted cup-shaped member 3l which is secured to the wall 36 as bywelding it thereto. Positioned in the cup-shaped member 3'! I provide ananti-friction bearing member 38 which engages the post 26.

The lower member 32 `comprises a body portion 39 whichincludes abottomwall ill having upturned side lianges 4I which at one end are directedupwardly and terminate in a horizontal semi-cylindrical portion 42 tomatch the semicylindrical portion 36 of the upper member 3l. The twosemi-cylindrical portions 36 and i2 of the .bracket 3l! surround a solidmetal plug 43 to which they are secured by a pair of rivets dit.

Positioned on the bottom wall lof the member 32 I` provide a cup-shapedmember l5 which is secured to the bottom wall by welding it thereto. Themember l5 is aligned with the upper Cup-Shaped member 31 and has ananti-friction bearing member 46 therein surrounding the post 29.

Intermediate the bearing 33 and the bearing 46 I provide a pulley wheel41 which is in the form of an inverted cup-shaped member including a topwall 48 having depending side flanges 49 which have a wide shallowgroove 59 therein. The top wall 43 of the wheel 41 is suitably aperturedto receive the post 26 and between the top wall 4B and the lower bearing46 I provide a hub member 5| which engages the inner raceway of thebearing 45.

rI'he hub 5I is apertured as at 52 to receive the post 26 and is securedto the wheel 41 by a screw 53. Between the upper wall 48 of the wheel`41 and the inner raceway of the upper bearing 38 I provide a washer 54.As shown in Fig. 7 the elbow portion I3 includes an upper arm supportingbracket 55 and a lower arm supporting bracket 55. The upper bracket 55includes a top wall 51 having depending side flanges 58 which at one endmerge into a'hollow cylindrical portion 59. (See Fig. 13). Positioned inthe cylindrical portion 59 I provide a metal plug 69 which is shown assecured to the bracket by rivets 9 I.

The upper elbow bracket 55 and the mast bracket 39 are connected by anarm member 62 which is formed of a predetermined length of seamlessmetal tubing. At one end of the arm the semi-cylindrical portions 36 and42 Vof the mast bracket 39 are positioned within the4 arm S2 and at theopposite end the cylindrical portion 59 of the elbow bracket 55 ispositioned within the arm 62.

Depending from the top wall 51 of the bracket 55 I provide an invertedcup-shaped member 93 which is secured to the bracket as by welding itthereto. Positioned in the member 63 I provide an anti-friction bearingmember 64 which is spaced from the upper wall of the member by a sleeve65 engaging the outer raceway.

The lower bracket 5B includes Ia bottom wall 66 having upturned sideflanges 61 which at oneend merge into a hollow cylindrical portion 58.(See Fig. 13). Positioned in the cylindrical portion 68 I provide ametal plug 69 which is secured to the bracket as by rivets 19. On thelower wall 68 I provide a cup-shaped member 1I which is aligned with theupper member 63 and is secured to the bracket 56 as by welding itthereto.

The lower wall 66 and the bottom wall of vthe member 1I are apertured asat 12. Positioned in the member 1| I provide an anti-friction bearingmember 13 which is spaced from the bottom wall by a washer 14 engagingthe outer raceway.

Journaled in the bearings 64 and 13 I provide a vertical shaft 15 havingan enlarged head 15 at the upper en-d which engages the upper end of theinner raceway of the bearing 64. Adjacent the lower end the shaftincludes a threaded portion 11 on which a nut 18 is positionedexteriorly of the bracket 56. Positioned in the aperture 12 andsurrounding the shaft 15 I provide a sleeve member 19 which engages thelower end of the inner raceway of the bearing 13 and is engaged by thenut 18.

Intermediate the bearings 64 and 13 I provide a double pulley member 8Dwhich includes an upper pulley portion 8| an-d a lower pulley portion82. Each of lthe portions 8| and 82 includes a central body portion 83having side fianges 84 in which a wide shallow groove 85 is provided.

The central portions 83 are cupped as at 89 one to receive the member 63and the other to receive the member 1 I. At the center the Centralportions 89 abut and are suitably apertured to receive the shaft 15.Surrounding the shaft 15 between the inner raceway of the bearing B4 andthe body of the upper pulley portion 8| I provide a washer 88 andsurrounding the shaft between the inner raceway of the bearing 13 andthe body of the lower pulley por-tion 83 I provide a washer 99. Theupper and lower pulley portions are secured together by screws 99.

Adapted to act upon the upper portion 9| of the Ypulley 89 I provide abrake member 9| which includes a threaded shank 92 positioned in athreaded aperture 93 in the top wall 51. The

. upper end of the shank 92 has an enlarged head 94 thereon and thelower end has a liber ydisk 95 mounted thereon which is adapted toengage the body portion 83 of the pulley portion 8|.

Opposite the brake member 9| I provide a similar brake member 96 whichis adapted to act upon the lower portion 82 of the pulley 89. The brakemember 99 includes a threaded shank 91 positioned in a threaded aperture98 in the bottom wall 69 of the lower bracket `55. At the lower end theshank 91 has 'an enlarged head 99 thereon and the upper end is tippedwith a ber member |99 which is adapted to engage the wall 83 of thelower portion 82 of the pulley 89.

The head portion I4 of the device I9 includes an arm supporting bracketI9I which includes a body portion |92 having depending side flanges |93which at one end merge into a hollow cylindrical portion |94. Positionedin the cylindrical portion |94 I provide a metal plug |95 which issecured to the bracket by rivets |99.

The head bracket IIlI and the lower elbow bracket 56 are connected by anarm member |91 which is formed of a predetermined length of seamlessmetal tubing. At one end of the arm the cylindrical portionl 69 of theelbow bracket 56 is positioned within the tubing and at the opposite endthe cylindrical portion |94 of the head bracket I9I is positioned withinthe tubing.

Depending from the top wall |93 of the bracket IDI I provide an invertedcup-shaped member |99 which is secured to the bracket as by welding itthereto. Positioned in the member |98 I provide an anti-friction bearingmember |99 Awhich is spaced from the top wall by a washer I I9 engagingthe outer raceway. Coaxial with the bearing |99 the top wall |03 has anaperture II2 therein.

Journaled in the bearing |99 I provide a hub member I|3 which at theupper end is threaded as at I|4 to receive a nut II5. The `hub II3 hasan aperture II6 therethrough and adjacent the lower end includes anenlarged elongated shoulder I I1 `and an enlarged head I I8. (See Fig.14). Positioned in the hub aperture IIB I provide a stem II9 whichadjacent the upper end includes a threaded portion |29 and adjacent-thelower en d a threaded portion I2I.` The threaded portion |29 of thestemreceives a cylindrical handle portion |22 which is secured theretoby a pin |23.

The head portion I4 includes a circular base plate |24 which includesnger portions .I 25 which are arranged at right angles to each other andwhich are adapted to receive the usual scale members such as commonlyused in connection with a imiversal drafting machine.

The central portion of the base plate |24 is cupped as at |26 andsuitably apertured to receive the stem I I9. A washer |21 is positionedbetween the inner surface of the cupped portion and the head I I8 of thehub and the base plate is secured to the stem |I9 b-y a nut |28 engagingthe stem threads' I 2|.

Depending from the base plate |24 I provide a plurality of foot bosses|25 which are secured to the base plate by screws |36.

Mounted on the horizontal nger |25 of the base plate |24 Iprovide arelease device ISI which is shown in detail in Fig; l2. As shown thedevice |3I includes a hubportion |32 having a threaded recess |33opening. through the bottom thereof. Above the hub |32 the deviceincludes an enlarged cam portion |36 (see Fig. 9) and above the camportion an enlarged iiange I 35. Above the ange the device includes athreaded hub |36 on which a handle member |31 is secured by a pin |38.The hub |32 of the device |3| is positioned in an aperture |38 of ab-olt member |39 which includes a threaded shank |49 positioned in athreaded aperture IM in the horizontal ringer portion |25. The device|3I is retained in position b-y a screw I 42 which engages the hubthreads |33 and the head of the screw engages a washer |43 which in.turn engages the bottom of the bolt |35. At the large portion thereofthe cam I3@ includes a shoulder I 44 which in one position is adapted toengage a stop pin |45 (see Fig. 9).

Above the base plate |24 I provide a stop plate |56 which has anelongated central aperture |41 therein to receive the shoulder I I1 ofthe hub I I3. The outer periphery of the plate |46 is notched as at U16which notches are spaced iifteen degrees apart completely around theperiphery.

Above the stop plate |46 I provide a protractc-r scale plate M9 theupper surface of which is graduated as at I 50. The scale plate |49 hasa central elongated aperture |5| therein to receive the shoulder I1 ofthe hub IIS. (See Fig. 14.) Above the scale plate |59 I provide asmaller disk |52 which has a central aperture therein to receive the hubI I3.

Positioned on the disk |52 I provide a pulley member |53 which includesa body portion |54 having depending side flanges I 55 the lo-wer edgesci which engage the disk |52. The upper portion of the side iianges |55have a shallow groove |56 therein. The body 55| includes a centraldished portion' |51 to receive the member |08 of the bracket IBI. Thecentral dished portion |51 has a disk I 5S secured thereto by screws |59and which engages the disk |52 and has a central aperture therein toreceive the hub I I 3 The pulley I 53 is secured to the disk |52 by aplurality of screws |65.

Surrounding the hub IIS between the upper surface'of the dished portionI5? and the inner raceway of the bearing I 69 I provide a washer IBI.Surrounding the hub ||3 and positioned in the aperture II 2 I provide asleeve member I 62 the lower end of which engages the inner raceway ofthe bearing |69 and the upper end is adapted to be engaged by the nut II 5. When the nut I I5 is tightened against the sleeve |62 theprotractor head assembly is rmly held in an `operative position.

Mounted on a projecting portion |63 of the base plate |24 I provide alatch member |64 which includes a body portion |65, an elongated arcuateneck portion |66 and ahead portion |61. The body portion |65 ispositioned on the base plate protuberance |63 and is secured thereto byrivets |66. The head portion 6I has a recess |69 therein the surface owhich is engaged by the cam |35 of the device ISI. The head portion |67further includes a protruding foot portion I1!) which is adapted to bepositioned in one of the notches |48 cent the periphery thereof.

of the stop plate |51 to prevent rotation of the plates M6 and |69relative to the base plate |24.

When the device |3|- is rotated in oney direction the cam |34 thereofforces the head |61 of the member |64 outward and the foot |16 out ofthe notch |48 whereupon the plates I IB and I 49 are free to rotaterelative to the baseplate I 24. For rigidly clamping theplate |66 to theplate |24 I provide a clamping device I 1| which is shown in detail inFig. 10. As shown the device I'II includes a vertical screw |12 theshank of which is positioned in threaded apertures |13 in the base plateprotuberance |63 and in the body portion |65 of the latch |64 with thehead engaging the under surface of the protuberance. Above the body |65I provide a clamp plate |14 which has an aperture |15 therein to receivethe screw |12 and includes a depending foot portion |16 adapted toengage the upper surface of the disk |56 adja- Above the plate |14 Iprovide a handle member |11 which has a threaded aperture |18 thereinAto receive the screw Iii.

When the handle |1'| is turned to move downward it forces the plate |15downward and the foot |16 into firm engagement with the plate I 46thereby preventing rotation of the platesl |46 and |49 relative to thebase plate |24.

For preventing rotation of the-pulley ISSrelative to the scale disk |49I provide a clamping device |86 which is shown in detail in Fig. 11. Asshown the device |86 includes a threaded vertical stud IilI which issecured to the scale plate |59 by riveting as indicated at |82. scaleplate |49 I provide a clamp plate |83 which has an aperture I 84 thereinto receive the stud IBI and includes an undercut portion I/I which is ofless depth than the thickness of the disk |52 a peripheral portion ofwhich is positioned therein. Abo-ve the clamp plate |83 I provide ahandle member |86 which has a threaded aperture |8`| therein toreceive'the threaded stud ISI.

When the handle |36 is rotated to move downward it forces the clampplate |83 downward which rmly clamps the disk |52 to the scale plate I'39.

The pulley |53 of the head portion It is connected to the lower pulleyportion of the elbow pulley 86 byV an endless strap member |96. Thestrap ISI) includes a length of metal which is` positioned in the groove85 of the pulley 86 and in the groove |56 of the pulley |53. rThe endsof the strap are joined vby an adjustable coupling device indicatedgenerally at |93 and shown in detail in Figs. 3 and 4. I v

The coupling |93 includes a body member |94 and a cylindrical member|95. The body |94 includes a knurled central portion |96 and hasathreaded recess |51' opening through one end with a reduced aperture |65opening through the opposite end and communicating with the threadedrecess i9? and forming a shoulder |98. v

The cylindrical member |95 includes an eX- ternally threaded portion |99which is positioned in the threaded recess |91 of the body |95 and areduced end hub 29|) having a slot 26| therein in which one end of thestrap |92 is positioned.

A head member 265| having an aperture 265 therein is positioned on thehub 266. The strap 92 is secured to the hub by a pin 2b?. Positioned inthe body |95 I provide a core member 268 which includes a cylindricalportion 269 positioned in the body aperture |98 and polygonal portionZIII which iits within a similarly shaped recess ZIE of they threadedportion |99. Intermediate the cylindrical portion 209 and the polygon-On the upper surface of the al portion 2 I 0 the core includes anenlarged collar 2|3. The cylindrical portion |99 has a slot 2M thereinin Which the other end of the strap |92 is positioned and securedthereto by pins 2 5.

When the body |94 is rotated all the slack in the strap |90 is taken up.By holding the head 294 stationary and rotating the body |94 the strapwill not twist as it is being tightened.

The upper pulley portion of the pulley 8D of the elbow portion 3 isconnected to the pulley 41 of the mast portion |2 by an endless strap2|5. The strap 2|5 is similar in all respects to the previouslydescribed strap |99 and like portions thereof are indicated by similarlyprimed reference numerals. The band |92'Aof the strap 2 5 is positionedin the groove of the pulley 80 and in the groove -50 of the pulley 41.

`In Fig. 15 I have shown a modified form of brake applied to the uppersection 55 of the elbow portion |3. When this type of biake is used therod 60 is replaced by a longer rod 22|) which extends inward to adjacentthe pulley 8| and is secured to the arm |52 by rivets 22|. The innerportionf4 of the rod 220 has an axial recess 222 therein opening throughthe inner end thereof. Adjacent the bottom of the recess 222 the rod 220has an angular transverse threaded aperture 223 therein which intersectsthe recess 222. Coaxial with the threaded rod aperture 223 the top 51 ofthe upper section 55 has a similar threaded aperture 224 therein.

Positioned in the rod recess 222 I provide a metal plunger 225 the innerend of which is conically tapered as indicated at 226. The outer end ofthe plunger 225 has a fiber disk 22E mounted thereon the end of which isshaped to engage the surface of the band recess 85 of the pulley 8|.

Positioned in the threaded apertures 223 and 224 I provide a threadedstem 221 the outer end of which has an enlarged knurled head 228thereon. The inner end of the stem 221 is conically tapered as at 229 tomatch the taper 226 of the plunger 225.

To apply braking friction to the pulley 8|v the stem 221 is rotated tomove downward and as it does it forces the plunger 225 outward towardsthe pulley 8| and the disc 225' into engagement with the pulley.

From the foregoing description it will be apparent that I have providedan improved universal drafting machine which may be economicallymanufactured and which is highly ecient in use.

Having thus described my invention I claim:

l. In a drafting machine, a base, an arm on the base, an elbow memberincluding an upper and a lower bracket, said arm engaging one of thebrackets, an anti-friction bearing supported by said upper bracket andan anti-friction bearing supported by said lowerbracket, a shaftjournaled in said anti-friction bearings, a double pulley membersurrounding said shaft, the upper and lower faces of said pulley beingrecessed to provide space for said bearings, said upper bracketincluding a body having depending side flanges spaced beyond saidpulley, said body and side flanges at one end merging into a reducedcylindrical portion, said lower bracket including a body having upturnedside flanges spaced beyond said pulley, said lower body and side flangesat one end merging int'oa reduced cylindrical portion, the top wall ofsaid upper bracket body having a threaded aperture, a threaded stempositioned in said aperture, an enlarged head on said stem above saidbody and a tip member on the opposite end of said stem adapted to engagethe upper face of said pulley, the bottom wall of said lower bracketbody having a threaded aperture, a threaded stem positioned in saidlower aperture, an enlarged head on said lower stem below said lowerbody, a tip member on the opposite end adapted to engage the lower faceof said pulley and a second arm on the other bracket.

2. In a drafting machine, a base, a pulley fixed on said base, an armrotatable on the base, an elbow on the first arm, a second arm on theelbow, said second arm including a pulley, a strap passing over saidpulleys and a coupling member for the ends of said strap, said couplingmember including a hollow cylindrical internally threaded body member, acore member rotatable on the body member and including a portionprojecting from the body member, means to secure one end of said strapto said projecting portion, and a threaded core member in the body,means permitting sliding engagement and preventing relative rotationbetween the two core members, means to secure the other end of the strapto the outer end of the threaded core member and a grip member upon theout'er end portion of the threaded core member. l

3. In a drafting machine, a base, a pulley fixed on said base, an armrotatable on the base, an elbow on the first arm, a second arm on theelbow, said second arm including a pulley, a strap passing over saidpulleys and a coupling member for the ends of said strap, said couplingmember including a hollow cylindrical internally threaded body memberhaving a shoulder at one end, a core member having a collar thereonengaging said shoulder and including a portion projecting from the bodymember, means to secure one end of said strap to said projectingportion, said core member including a polygonal portion disposed withinthe body member and a threaded core member in the body and having arecess securing the portion on the first core member, means to securethe other end of the strap to the outer end of the threaded core memberand a collar member secured upon the outer end of the threaded coremember.

4. In a drafting machine, a base, a bracket rotatable on said base, anarm on said bracket, an elbow member support on said arm, said elbowmember including a pair of pulleys, one of said pulleys having a groovedperiphery, a rod mounted on said arm and extending to a point adjacentsaid one pulley, said rod having a recess adjacent the pulley, a plungerslidable in said recess and adapted to engage in said groove, said rodhaving a threaded lateral recess intersecting said first mentionedrecess, a threaded member in said lateral recess, said threaded memberhaving a cam at its inner end and said plunger having a cam engagingsaid threaded member cam.

5. In a drafting machine, a base, an arm on the base, an elbow member,said elbow including an upper bracket and a lower bracket, opposed cupmembers on each bracket, spacing sleevesv in said cup members, said armengaging one of said brackets, an anti-friction bearing supported ineach cup member and engaging the spacing sleeves, a shaft journaled insaid anti-friction bearings, a double pulley member surrounding saidshaft, said double pulley including two contacting disk-like centralportions and offset strap engaging portions, the offset portionsproviding spaces for said bearings, means to clamp said pulley centralportions between the upper and lower bearings, and a second arm engagingthe other bracket.

6. In a drafting machine, a base, an arm on the base, an elbow memberincluding an upper and a lower bracket, said arm engaging one of thebrackets, an anti-friction bearing supported by said upper bracket andan anti-friction bearing supported by said lower bracket, a shaftjournaled in said anti-friction bearings, a double pulley membersurrounding said shaft, said upper bracket including a body havingdepending side flanges spaced beyond said pulley, said body and sideflanges at one end merging into a reduced cylindrical portion, saidlower bracket including a body having upturned side anges spaced beyondsaid pulley, said lower body and side flanges at one end merging into areduced cylindrical portion, the top wall of said upper bracket bodyhaving an aperture, a stem positioned inv said aperture, an enlargedhead on said stem above said body and a tip member on the opposite endof said stem adapted to engage the upper face of said pulley, the bottomwall'of said lower bracket body having an aperture, a stem positioned insaid last mentioned aperture, an enlarged head on said lower stem'belowsaid lower body, a tip member on the opposite end adapted to engage thelower face of said pulley and a second arm on the other bracket.

RUSSELL H. GARNER.

